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Inter-Regional Tech Complementarity:A Mechanism for Balanced Development and GVC Upgrading
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作者 Zheng Jianghuai Jin Shengnan 《China Economist》 2026年第1期2-32,共31页
In the complex architecture of global value-chain(GVC)trade,firms’technological content increasingly reflects external knowledge flows.This study examines how inter-regional technological complementarity shapes firms... In the complex architecture of global value-chain(GVC)trade,firms’technological content increasingly reflects external knowledge flows.This study examines how inter-regional technological complementarity shapes firms’GVC advancement,measured by the domestic value-added rate(DVAR)in exports.Using integrated Chinese microdata(2000-2014),we find this complementarity significantly boosts export DVAR,explaining about one-quarter of its observed growth.Two mechanisms drive this effect:increased use of domestic intermediates and gains in firm productivity.The benefits are especially large for firms with lower human capital and for those in accessible,innovation-peripheral regions,helping narrow productivity gaps across firms and space.Affected firms also exhibit broader export scopes,higher product quality,more diversified destinations,and greater markups-firm-level evidence of GVC upgrading.These findings highlight how external technological linkages drive upgrading and underscore the importance of fostering inter-regional synergies for balanced development. 展开更多
关键词 technological complementarity global value chains domestic value-added rate(DVAR) balanced regional development
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Gut microbial characteristics of the damp-heat constitution:a population-based multicenter cross-sectional study 被引量:2
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作者 LI Tianxing ZHU Linghui +9 位作者 WANG Xueke TANG Jun YANG Lingling PANG Guoming LI Huang WANG Liying DONG Yang ZHAO Shipeng LI Yingshuai LI Lingru 《Journal of Traditional Chinese Medicine》 2025年第1期140-151,共12页
OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which... OBJECTIVE:To investigate the difference in gut microbiota between population with damp-heat constitution(DHC)and balanced constitution(BC).METHODS:A multi-centered cross-sectional casecontrol study was conducted,which included 249 participants with damp-heat constitution or balanced constitution.Baseline information of participants was collected,and stool samples were collected for gut microbiota analysis.Principal coordinate analysis,linear discriminant analysis effect size analysis,receiver operating characteristic,random forest model,and phylogenetic investigation of communities by reconstruction of unobserved states methods were used to reveal the relationship between gut microbiota and the damp-heat constitution.RESULTS:Compared to those in the BC group,the richness and diversity of the microbiota,specifically those of several short-chain fatty acid producing genera such as Barnesiella,Coprobacter,and Butyricimonas,were significantly decreased in the DHC group.Regarding biological functions,flavonoid biosynthesis,propanoate metabolism,and nucleotide sugar metabolism were suppressed,while arachidonic acid metabolism and glutathione metabolism were enriched in the DHC group.Finally,a classifier based on the microbiota was constructed to discriminate between the DHC and BC populations.CONCLUSION:The gut microbiota of the DHC population exhibits significantly reduced diversity and is closely related to inflammation,metabolic disorders,and liver steatosis,which is consistent with clinical observations,thus serving as a potential diagnostic tool for traditional Chinese medicine constitution discrimination. 展开更多
关键词 damp-heat constitution balanced constitution Traditional Chinese medicine constitution MICROBIOTA inflammatory PICRUSt multicenter study cross-sectional studies
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Fluid therapy in acute pancreatitis comparing balanced solutions and normal saline:A systematic review,meta-analysis and trial sequential analysis 被引量:1
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作者 Lin Gao Hsiang-Wei Wang +4 位作者 Zi-Rui Liu Yi-Zhen Xu Lu Ke Wei-Qin Li John A Windsor 《Hepatobiliary & Pancreatic Diseases International》 2025年第4期371-380,共10页
Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the t... Background:Isotonic crystalloids are recommended as the first choice for fluid therapy in acute pan-creatitis(AP),with normal saline(NS)and lactate Ringer’s(LR)used most often.Evidence based recom-mendations on the type of fluid are conflicting and generally come from small single-center randomized controlled trials(RCTs).We therefore conducted a systematic review and meta-analysis to compare the effect of balanced solutions(BS)versus NS on patient-centered clinical outcomes in AP.Methods:From four databases searched up to October 2024,we included only RCTs of adult patients with AP that compared the use of BS(including LR,acetate Ringer’s,etc.)with NS.The primary out-come was the disease advances from AP to moderately severe and severe AP(MSAP/SAP).Trial sequential analyses(TSA)were conducted to control for type-I and type-II errors and Grading of Recommendations Assessment,Development,and Evaluation(GRADE)was used to assess the quality of evidence.Results:Six RCTs were identified and included,involving 260 patients treated with BS and 298 patients with NS.Patients who received the BS had less MSAP/SAP[odds ratio(OR)=0.50,95%confidence in-terval(CI):0.29 to 0.85,P=0.01,I^(2)=0%;5 studies,299 patients],reduced the need of ICU admission(OR=0.60,95%CI:0.39 to 0.93,P=0.02,I^(2)=0%;5 studies,507 patients)and shorter length of hospital stay[mean difference(MD)=-0.88,95%CI:-1.48 to-0.28,P=0.004,I^(2)=0%;6 studies,558 patients;confirmed by TSA with high certainty]compared with those who received NS.The evidence for most of the clinical outcomes was rated as moderate to low due to the risk of bias,imprecision and inconsistency.Conclusions:BS,compared with NS,was associated with improved clinical outcomes in patients with AP.However,given the moderate to low quality of evidence for most of the outcomes assessed,further trials are warranted. 展开更多
关键词 Acute pancreatitis Fluid therapy Normal saline Balanced solution Systematic review
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China Can Achieve Carbon Neutrality in Line with the Paris Agreement's 2℃Target:Navigating Global Emissions Scenarios,Warming Levels,and Extreme Event Projections 被引量:1
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作者 Xiaoye Zhang Junting Zhong +4 位作者 Xiliang Zhang Da Zhang Changhong Miao Deying Wang Lifeng Guo 《Engineering》 2025年第1期207-214,共8页
This paper proposes that China,under the challenge of balancing its development and security,can aim for the Paris Agreement's goal to limit global warming to no more than 2℃by actively seeking carbonpeak and car... This paper proposes that China,under the challenge of balancing its development and security,can aim for the Paris Agreement's goal to limit global warming to no more than 2℃by actively seeking carbonpeak and carbon-neutrality pathways that align with China's national conditions,rather than following the idealized path toward the 1.5℃target by initially relying on extensive negative-emission technologies such as direct air carbon capture and storage(DACCS).This work suggests that pursuing a 1.5℃target is increasingly less feasible for China,as it would potentially incur 3–4 times the cost of pursuing the 2℃target.With China being likely to achieve a peak in its emissions around 2028,at about 12.8 billion tonnes of anthropogenic carbon dioxide(CO_(2)),and become carbon neutral,projected global warming levels may be less severe after the 2050s than previously estimated.This could reduce the risk potential of climate tipping points and extreme events,especially considering that the other two major carbon emitters in the world(Europe and North America)have already passed their carbon peaks.While natural carbon sinks will contribute to China's carbon neutrality efforts,they are not expected to be decisive in the transition stages.This research also addresses the growing focus on climate overshoot,tipping points,extreme events,loss and damage,and methane reductions in international climate cooperation,emphasizing the need to balance these issues with China's development,security,and fairness considerations.China's pursuit of carbon neutrality will have significant implications for global emissions scenarios,warming levels,and extreme event projections,as well as for climate change hotspots of international concern,such as climate tipping points,the climate crisis,and the notion that the world has moved from a warming to a boiling era.Possible research recommendations for global emissions scenarios based on China's 2℃target pathway are also summarized. 展开更多
关键词 Climate change 2℃target Carbon neutrality Emission scenarios Balanced mitigation
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A prototype of 2μm balanced detector for space-borne Coherent Doppler Wind Lidar
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作者 CHEN Bao-Lin JIN Ge +2 位作者 WANG Chong CHEN Lian 《红外与毫米波学报》 北大核心 2025年第6期1021-1029,共9页
Despite rapid advancements in lidar technology,extremely long-range observation remains a signifi⁃cant challenge.Recently,2μm lasers have demonstrated a potential to be applied in CDWL(Coherent Doppler Wind Lidar)sys... Despite rapid advancements in lidar technology,extremely long-range observation remains a signifi⁃cant challenge.Recently,2μm lasers have demonstrated a potential to be applied in CDWL(Coherent Doppler Wind Lidar)system,for its high atmospheric penetration capability through the atmosphere and high potential la⁃ser power.In this study,we present a 2μm balanced detector that consists of a pair of commercial positive-intrin⁃sic-negative(PIN)diodes with a low-noise transimpedance circuit.To meet the high bandwidth requirements,the highspeed transimpedance circuit and bias voltage tuning method were utilized to overcome the large capaci⁃tance of PIN diodes.The circuit transfer function,stability analysis and noise calculation have been studied.The detector was co-packaged with a data acquisition module for convenient data transmission and bias voltage con⁃trol.The characteristics of the detector,including bandwidth,noise and bias voltage influence,are evaluated in laboratory.Results show that the RMS value of the balanced detector background noise is 539μV and the band⁃widths of the two diodes are 110.8 MHz and 110.3 MHz,respectively.The evaluation results show that the bal⁃anced detector meets the wind measurement requirements and allows for a 1.45×increase in bandwidth through bi⁃as voltage tuning.Our work offers insights into lidar detector design and bandwidth enhancement,providing a valuable reference for researchers and professionals in the field.More importantly,it lays a critical foundation for fu⁃ture ultra-long-range and space-borne 2μm coherent wind lidar systems by addressing key device-level challenges. 展开更多
关键词 balanced detector transimpedance circuit CDWL laser detection
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Parks:Heartbeat of the city
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作者 孙朝岚 《疯狂英语(新读写)》 2025年第9期15-17,75,共4页
Living in a city often means dealing with noise,pollution and a hectic schedule.Parks offer a necessary relaxation from the urban chaos,providing a peaceful environment where individuals can relax and connect with nat... Living in a city often means dealing with noise,pollution and a hectic schedule.Parks offer a necessary relaxation from the urban chaos,providing a peaceful environment where individuals can relax and connect with nature.These green spaces are essential for promoting a balanced and healthy lifestyle among city residents. 展开更多
关键词 parks green spaces balanced lifestyle nature connection RELAXATION urban chaos promoting balanced healthy lifestyle healthy lifestyle
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High-Order Common-Mode and Differential-Mode Reflectionless Balanced Bandpass Filters with Improved Selectivity and Out-of-Band Rejection
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作者 Zhang Yifan Wu Yongle +2 位作者 Wang Weimin Xu Ruoxi Cai Yuanlong 《China Communications》 2025年第8期87-101,共15页
High-selectivity common-mode(CM)and differential-mode(DM)reflectionless balanced bandpass filters(BBPFs)are proposed in this article.By loading absorption networks at single/both ends of the basic ring resonator,input... High-selectivity common-mode(CM)and differential-mode(DM)reflectionless balanced bandpass filters(BBPFs)are proposed in this article.By loading absorption networks at single/both ends of the basic ring resonator,input-/two-port wideband CM and DM reflectionless performance,wideband filtering performance and all-stop CM suppression are obtained.The absorption network composed of K-sections of coupled-lines(CLs)terminated with grounded resistors can not only extend the filtering performance to high order,but also realize wideband absorption of CM noise and out-of-band DM signals.Absorptive stubs are loaded at ports to increase the design flexibility and enhance the absorption.As for the input-reflectionless type,multiple independently controlled transmission zeros(TZs)are obtained by the TZ control network to improves the selectivity and out-of-band rejection.A set of 2 GHz micro-strip BBPFs are designed and measured,which shows simultaneous CM and DM absorption performance. 展开更多
关键词 balanced filter grounded resistors highorder high-selectivity reflectionless filter ring resonator
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A novel optimization scheme for structure and balance of compound balanced beam pumping units using the PSO, GA, and GWO algorithms
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作者 Jie Wang Quan-Ying Guo +3 位作者 Cheng-Long Fu Gang Dai Cheng-Yu Xia Li-Qin Qian 《Petroleum Science》 2025年第3期1340-1359,共20页
The beam pumping unit(BPU)remains the most stable and reliable equipment for crude oil lifting.Despite its simple four-link mechanism,the structural design of the BPU presents a constrained single-objective optimizati... The beam pumping unit(BPU)remains the most stable and reliable equipment for crude oil lifting.Despite its simple four-link mechanism,the structural design of the BPU presents a constrained single-objective optimization problem.Currently,a comprehensive framework for the structural design and optimization of compound balanced BPUs is lacking.Therefore,this study proposes a novel structural design scheme for BPUs,aiming to meet the practical needs of designers and operators by sequentially optimizing both the dynamic characteristics and balance properties of the BPUs.A dynamic model of compound balanced BPU was established based on D'Alembert's principle.The constraints for structural dimensions were formulated based on the actual operational requirements and design experience with BPUs.To optimize the structure,three algorithms were employed:the particle swarm optimization(PSO)algorithm,the genetic algorithm(GA),and the gray wolf optimization(GWO)algorithm.Each newly generated individuals are regulated by constraints to ensure the rationality of the outcomes.Furthermore,the integration of three algorithms ensures the increased likelihood of attaining the global optimal solution.The polished rod acceleration of the optimized structure is significantly reduced,and the dynamic characteristics of the up and down strokes are essentially symmetrical.Additionally,these three algorithms are also applied to the balance optimization of BPUs based on the measured dynamometer card.The calculation results demonstrate that the GWO-based optimization method exhibits excellent robustness in terms of structural optimization by enhancing the operational smoothness of the BPU,as well as in balance optimization by achieving energy conservation.By applying the optimization scheme proposed in this paper,the CYJW7-3-23HF type of BPU was designed,achieving a maximum polished rod acceleration of±0.675 m/s^(2) when operating at a stroke of 6 min^(−1).When deployed in two wells,the root-mean-square(RMS)torque was minimized,reaching values of 7.539 kN·m and 12.921 kN·m,respectively.The proposed design method not only contributes to the personalized customization but also improves the design efficiency of compound balanced BPUs. 展开更多
关键词 Compound balanced BPU Dynamic model Structural optimization Balance optimization CONSTRAINTS
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Prenatal diagnosis of balanced translocation from three families:Six case reports
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作者 Xun Kan Yu-Xin Xie +6 位作者 Lan Yao Lu-Yao Wang Yu-Xin Xia Jian-Qiao Sun Ming-Lei Bian Liang Yu Ying-Li Lu 《World Journal of Clinical Cases》 2025年第20期35-41,共7页
BACKGROUND Carriers of chromosomal balanced translocations are often physically healthy with no obvious developmental problems.However,potential chromosomal imbalance in their gametes can lead to implantation failure,... BACKGROUND Carriers of chromosomal balanced translocations are often physically healthy with no obvious developmental problems.However,potential chromosomal imbalance in their gametes can lead to implantation failure,miscarriage,or the birth of a child with a chromosomal abnormality.CASE SUMMARY We report six cases of chromosomal translocations involving three families,including the specific Robertson(Roche)translocation.Case 1:The karyotype of the proband was 46,XX,t(18;19)(q22;p12).Case 2:Interventional prenatal diagnosis at 18 weeks of gestation confirmed that the karyotype of the fetus was 46,XY,t(18;19)(q22;p12).Case 3:The karyotype of the proband was 46,XY,t(5;18)(p13;p11).Case 4:Interventional prenatal diagnosis at 14+6 weeks confirmed that the karyotype of the fetus was 46,XX,der(18)t(5;18)(p13;p11)pat.Case 5:The karyotype of the proband was 45,XY,der(14;22)(q10;q10).Case 6:Interventional prenatal diagnosis at 19+4 weeks confirmed that the karyotype of the fetus was 45,XX,rob(14;22)(q10;q10).CONCLUSION Carriers of chromosomal translocations have a high risk of adverse pregnancy outcomes,though they can still have normal offspring.This report on six cases of chromosomal translocations from three families could serve as a reference for future prenatal diagnosis of chromosomal translocations and decision-making on whether to continue the pregnancy. 展开更多
关键词 Chromosomal translocation Prenatal diagnosis Balanced translocation Robertson translocation Case report
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Balanced Optimization of Dimensional Accuracy and Printing Efficiency in FDM Based on Data-Driven Modeling
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作者 Liu Changhui Li Hao +5 位作者 Yu Chunlong Liao Xueru Liu Xiaojia Sun Jianzhi Tang Qirong Yu Min 《Additive Manufacturing Frontiers》 2025年第2期97-110,共14页
Additive manufacturing(AM),particularly fused deposition modeling(FDM),has emerged as a transformative technology in modern manufacturing processes.The dimensional accuracy of FDM-printed parts is crucial for ensuring... Additive manufacturing(AM),particularly fused deposition modeling(FDM),has emerged as a transformative technology in modern manufacturing processes.The dimensional accuracy of FDM-printed parts is crucial for ensuring their functional integrity and performance.To achieve sustainable manufacturing in FDM,it is necessary to optimize the print quality and time efficiency concurrently.However,owing to the complex interactions of printing parameters,achieving a balanced optimization of both remains challenging.This study examines four key factors affecting dimensional accuracy and print time:printing speed,layer thickness,nozzle temperature,and bed temperature.Fifty parameter sets were generated using enhanced Latin hypercube sampling.A whale optimization algorithm(WOA)-enhanced support vector regression(SVR)model was developed to predict dimen-sional errors and print time effectively,with non-dominated sorting genetic algorithm Ⅲ(NSGA-Ⅲ)utilized for multi-objective optimization.The technique for Order Preference by Similarity to Ideal Solution(TOPSIS)was applied to select a balanced solution from the Pareto front.In experimental validation,the parts printed using the optimized parameters exhibited excellent dimensional accuracy and printing efficiency.This study comprehensively considered optimizing the printing time and size to meet quality requirements while achieving higher printing efficiency and aiding in the realization of sustainable manufacturing in the field of AM.In addition,the printing of a specific prosthetic component was used as a case study,highlighting the high demands on both dimensional precision and printing efficiency.The optimized process parameters required significantly less printing time,while satisfying the dimensional accuracy requirements.This study provides valuable insights for achieving sustainable AM using FDM. 展开更多
关键词 Fused deposition modeling Dimensional accuracy Process parameters Printing efficiency Balanced optimization Sustainable manufacturing
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神奇的地中海饮食
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《疯狂英语(新读写)》 2025年第6期4-8,74,共6页
Have you found an antiaging solution?It has been a subject of interest in many studies.Even if there is no treatment on the market that can prove an effective method to slow human aging,research shows that the consump... Have you found an antiaging solution?It has been a subject of interest in many studies.Even if there is no treatment on the market that can prove an effective method to slow human aging,research shows that the consumption of low calories and a balanced diet can help to boost our immune system. 展开更多
关键词 immune system balanced diet boost our immune system Mediterranean diet consumption low calories aging ANTIAGING low calorie intake
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Effect of amino acid-balanced diet-based nutritional-psychological intervention on muscle wasting and quality of life in cirrhosis patients
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作者 Wei-Wei Zhuge Lin-Xiu Zheng +2 位作者 Li-Juan Xu Si-Fang Zhou Hai-Xin Yao 《World Journal of Psychiatry》 2025年第11期231-239,共9页
BACKGROUND Patients with liver cirrhosis often experience muscle wasting that significantly affects their quality of life.AIM To investigate the effects of comprehensive nutritional and psychological interventions bas... BACKGROUND Patients with liver cirrhosis often experience muscle wasting that significantly affects their quality of life.AIM To investigate the effects of comprehensive nutritional and psychological interventions based on an amino acid-balanced diet on muscle wasting and quality of life in patients with liver cirrhosis.METHODS A retrospective study of 130 patients with liver cirrhosis(May 2023 to June 2024)was divided into control(conventional treatment,n=65)and observational groups(conventional+amino acid-balanced nutrition and psychological intervention,n=65).Anxiety(Self-Rating Anxiety Scale),depression(Self-Rating Depression Scale),lower limb muscle strength,and quality of life(Chronic Liver Disease Questionnaire)were assessed pre-intervention,and 3/6 months postintervention.RESULTS At baseline,no significant differences were observed between the two groups in terms of age,sex,etiology of cirrhosis,disease duration,disease severity,or any other measured outcome(P>0.05).At 3 months and 6 months post-intervention,the observational group exhibited significantly lower Self-Rating Anxiety Scale and Self-Rating Depression Scale scores than the control group(P<0.05),indicating reduced anxiety and depression as well as higher grip strength and increased lower limb muscle strength(P<0.05).Additionally,the observational group demonstrated superior Chronic Liver Disease Questionnaire scores across all domains, reflecting an improved quality of life (P < 0.05).CONCLUSIONAn amino acid-balanced diet and psychological intervention can effectively alleviate anxiety and depression andimprove muscle strength and quality of life in patients with cirrhosis and are worthy of clinical promotion. 展开更多
关键词 CIRRHOSIS SARCOPENIA Amino acid balanced diet Nutritional psychological intervention Quality of life
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Digital twin-based structural health monitoring and measurements of dynamic characteristics in balanced cantilever bridge
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作者 Tidarut Jirawattanasomkul Le Hang +4 位作者 Supasit Srivaranun Suched Likitlersuang Pitcha Jongvivatsakul Wanchai Yodsudjai Punchet Thammarak 《Resilient Cities and Structures》 2025年第3期48-66,共19页
This study developed a digital twin(DT)and structural health monitoring(SHM)system for a balanced cantilever bridge,utilizing advanced measurement techniques to enhance accuracy.Vibration and dynamic strain measuremen... This study developed a digital twin(DT)and structural health monitoring(SHM)system for a balanced cantilever bridge,utilizing advanced measurement techniques to enhance accuracy.Vibration and dynamic strain measurements were obtained using accelerometers and piezo-resistive strain gauges,capturing low-magnitude dynamic strains during operational vibrations.3D-LiDAR scanning and Ultrasonic Pulse Velocity(UPV)tests captured the bridge's as-is geometry and modulus of elasticity.The resulting detailed 3D point cloud model revealed the structure's true state and highlighted discrepancies between the as-designed and as-built conditions.Dynamic properties,including modal frequencies and shapes,were extracted from the strain and acceleration measurements,providing critical insights into the bridge's structural behavior.The neutral axis depth,indicating stress distribution and potential damage,was accurately determined.Good agreement between vibration measurement data and the as-is model results validated the reliability of the digital twin model.Dynamic strain patterns and neutral axis parameters showed strong correlation with model predictions,serving as sensitive indicators of local damage.The baseline digital twin model and measurement results establish a foundation for future bridge inspections and investigations.This study demonstrates the effectiveness of combining digital twin technology with field measurements for real-time monitoring and predictive maintenance,ensuring the sustainability and safety of the bridge infrastructure,thereby enhancing its overall resilience to operational and environmental stressors. 展开更多
关键词 Digital twin Structural health monitoring Balanced cantilever bridge 3D-LiDAR Dynamic strain measurement
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Narrowing Regional Gaps:A Study on the Strategies for Balanced Development of Regional Education in China
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作者 Siqi Wang Yuanyuan Jia +3 位作者 Geman Gao Chang Tian Feng Yu Yu Cai 《Journal of Contemporary Educational Research》 2025年第10期37-41,共5页
By comprehensively analyzing the current status of education development and the achievements of economic development in China,this paper reveals the synergistic effect between the overall improvement of education lev... By comprehensively analyzing the current status of education development and the achievements of economic development in China,this paper reveals the synergistic effect between the overall improvement of education levels and economic growth.The paper points out that although the increase in educational investment has provided talent support for economic development,the imbalance in regional education development still exists.Furthermore,the paper explores the two-way promotion mechanism between education and economic development,and proposes a series of strategies,including balanced layout,targeted support,and innovation-driven development,to achieve the coordinated and balanced development of regional education and narrow regional gaps.These strategies aim to optimize the allocation of educational resources,improve the quality of education,and promote the all-round progress of the economy and society. 展开更多
关键词 Regional gaps Regional education Coordinated and balanced development
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Long time hybrid integration of radar rotating target
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作者 SONG Zhiyong XU Yuntao 《Journal of Systems Engineering and Electronics》 2025年第6期1477-1487,共11页
In the traditional radar unmanned aerial vehicle(UAV)detection process,coherent integration and micro-Doppler(m-D)parameter estimation are carried out separately.The target discrimination process needs to obtain the p... In the traditional radar unmanned aerial vehicle(UAV)detection process,coherent integration and micro-Doppler(m-D)parameter estimation are carried out separately.The target discrimination process needs to obtain the position information of the target,which will lose energy.In this paper,a long time integration method of radar signal based on rotating target radon Fourier transform(RTRFT)is proposed.This method modifies the distance and frequency terms in the traditional generalized radon Fourier transform(GRFT),and adds the frequency sinusoidal modulation term.Then,based on the cardinality balanced multi-target multi-Bernoulli(CBMeMBer)filter,the position of the target is detected in the high-dimensional space obtained by RTRFT.This method can combine coherent integration and micro-motion parameter estimation.Simulation experiments show that the proposed method can estimate the main translational parameters and rotational micro-motion parameters of the target while detecting the target,and the target detection performance is improved. 展开更多
关键词 long time coherent integration(LTCI) cardinality balanced multi-agent multi-Bernoulli filter signal detection unmanned aerial vehicle(UAV) generalized radon Fourier transform(GRFT)
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Demonstration and performance evaluation of reconfigurable multiband microwave filters using a programmable photonic integrated circuit
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作者 ASHITOSH VELAMURI KUMAR PIYUSH +6 位作者 YASH RAJ ARNAB GOSWAMI ANANDHA PADMANABHAN NITIN GHODGAONKAR DINANATH SONI JANAKIRAMAN VIRARAGHAVAN BIJOY KRISHNA DAS 《Photonics Research》 2025年第12期3341-3361,共21页
A programmable silicon photonic multiband microwave filter with tunable bandwidths has been demonstrated.The filter has been successfully used to set up a radio-over-fiber link operating in the X-band as a proof of co... A programmable silicon photonic multiband microwave filter with tunable bandwidths has been demonstrated.The filter has been successfully used to set up a radio-over-fiber link operating in the X-band as a proof of concept.For this purpose,we have investigated the programmable photonic integrated circuit comprising 14 tunable balanced Mach–Zehnder interferometers designed into a square mesh architecture and fabricated using CMOS-compatible silicon photonic technology. 展开更多
关键词 programmable silicon photonic multiband microwave filter programmable photonic integrated circuit balanced Mach Zehnder interferometers CMOS compatible silicon photonic technology square mesh architecture radio fiber link reconfigurable multiband microwave filters
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Effects of N,P and K Fertilizers on Photosynthetic Characteristics of Mulberry 被引量:2
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作者 黄盖群 危玲 +6 位作者 佟万红 高辉 殷浩 刘刚 张烈 孔繁慧 罗春燕 《Agricultural Science & Technology》 CAS 2012年第12期2562-2568,共7页
[Objective] The aim was to research the effects of N, P and K fertilizers on photosynthetic characteristics of mulberry. [Method] In the test, Chuan 826, a va- riety of mulberry, was taken as an example to explore the... [Objective] The aim was to research the effects of N, P and K fertilizers on photosynthetic characteristics of mulberry. [Method] In the test, Chuan 826, a va- riety of mulberry, was taken as an example to explore the relationships of chloro- phyll content, leaf area index, net photosynthetic rate, stomatal conductance of leaf, CO2 concentration of cells in leaves and transpiration rate with N, P and K fertilizers at different quantities. [Result] N, P and K fertilizers at different quantities have ef- fects on photosynthetic indices. In detail, N, P and K fertilizer at appropriate quanti- ties enhanced LAI, Chla+b, Pn, Cond and Tr, Ci of mulberry leaves in control group without fertilizers was significantly higher than that in treatment groups. N, P and K at proper quantities (N at 600 kg/hm2, P at 210 kg/hm2 and K at 300 kg/hm2) would keep functional leaves well and higher photosynthetic period for a long term. [Conclusion] The research explored adjustment of photosynthetic characteristics and differ- ent treatments on photosynthesis of mulberry, providing reference for construction of excellent and highly-qualified mulberry garden. 展开更多
关键词 MULBERRY Balanced fertilization Photosynthetic characteristics
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A4~12GHz Wideband Balanced MIC Power Amplifier 被引量:1
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作者 姚小江 李滨 +2 位作者 刘新宇 陈中子 陈晓娟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1868-1871,共4页
A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz cente... A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz center frequency with an associated gain of 8.5dB and a gain flatness of + /- 0.6dB in the 4-12GHz frequency range. 展开更多
关键词 WIDEBAND Lange coupler microwave integrated circuit balanced power amplifiers
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Effects of Balanced Fertilization on Mulberry Leaf Quality and Its Active Substance Content 被引量:1
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作者 黄盖群 张烈 +6 位作者 殷浩 危玲 佟万红 刘刚 张建华 林超文 郭涛 《Agricultural Science & Technology》 CAS 2013年第4期635-639,644,共6页
This paper study the effect of nitrogen (N, X1), phosphorus (P, X2) and potassium (K, X3) in different amounts on crude protein, soluble sugar, total flavonoid and 1-deoxynojirimycin contents in mulberry leaves,... This paper study the effect of nitrogen (N, X1), phosphorus (P, X2) and potassium (K, X3) in different amounts on crude protein, soluble sugar, total flavonoid and 1-deoxynojirimycin contents in mulberry leaves, with mulberry trees in spring and autumn as the material and as per "3414" experimental design. The results showed that the qualities and active substance content of mulberry leaves changed from increasing to decreasing with its development; crude protein and solu-ble sugar achieved the peak on August 20; total flavonoid and 1-deoxynojirimycin was the highest on May 15. Fertilizations with N, P and K fertilizers at different amounts had significant effects on quality of mulberry leaf and content of active substances. Specifically, as fertilizer amount increased, the content of active sub- stances grew dramatically and achieved the highest at level 2 (X^2X=X~_). Based on fertilizer effect functions of objective yield, the recommended amounts of N, P and K fertilizers based on crude protein, soluble sugar, flavonoid content and DNJ in test sites were 718.46, 220.11 and 305.23 kg/hm2, when the highest of crude protein in mulberry leaf was 1 813.83 kg/hm2. When N, P and K fertilizers were recommended at 666.54, 204.41 and 243.18 kg/hm2, soluble sugar in mulberry leaf achieved the peak at 1 042.65 kg/hm2. When N, P and K fertilizers were at 675.96, 326.49 and 462.90 kg/hm2, flavonoid content achieved the maximum at 147.90 kg/hm2. When N, P and K fertilizers were at 720.9, 225.11 and 323.63 kg/hm2, DNJ content was the highest at 13.55 kg/hm2. 展开更多
关键词 MULBERRY Balanced fertilization QUALITY Active substances
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Effects of Slow-release Fertilizer and Balanced Fertilization on Nitrogen, Phosphorus and Potassium Uptake in Peppers 被引量:1
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作者 张忠武 王建新 +4 位作者 鲁耀 段宗颜 彭荣珍 周敏 杨景华 《Agricultural Science & Technology》 CAS 2015年第7期1457-1461,共5页
Field plot experiment was conducted to study the effects of two slow-re- lease fertilizers and balanced fertilization on dry matter accumulation, yield, fertilizer use efficiency, nitrogen, phosphorus and potassium up... Field plot experiment was conducted to study the effects of two slow-re- lease fertilizers and balanced fertilization on dry matter accumulation, yield, fertilizer use efficiency, nitrogen, phosphorus and potassium uptake of peppers at Jiangna Town, Yanshan County, Yunnan Province in 2011. The results showed that the dry matter accumulation in dried pepper plant, pepper yield, nitrogen, phosphorus, potassium uptake in peppers were significantly increased in all the fertilizer treat- ments, compared with those in control (no fertilizer). Compared with conventional fertilization, balanced fertilization, slow-release compound fertilizer and slow-release urea fertilizer significantly increased dried pepper economic output by 20.94%, 17.5% and 14.54%, nitrogen uptake in dried peppers by 21.53%,18.46% and 13.19%, phosphorus uptake in dried peppers by 14.08%, 15.76% and 10.44%, potassium uptake in dried peppers by 22.66%, 15.73% and 16.28%; they also in- creased nitrogen and potassium use efficiency, but reduced potassium use efficiency due to the increased potassium addition. In treatments with balanced fertilization, slow-release compound fertilizer and slow-release urea fertilizer, the nitrogen utiliza- tion was 5.84%, 7.14% and 8.33% higher and the phosphorus utilization was 3.32%, 3.27% and 2.47% higher than those in treatment with conventional fertiliza- tion. In addition, the nitrogen application could be reduced by 20%-50% by bal- anced fertilization and the two slow-release fertilizers, thereby reducing environmen- tal pollution. Slow-release fertilizers could also reduce the frequency of fertilization and labor costs. 展开更多
关键词 Slow-release fertilizer Balanced fertilization Dried pepper NPK uptake Fertilizer use efficiency
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